1. Field of the Invention
The invention relates to a process and a device for welding a thermoplastic stiffener to a skin. The invention more particularly, but not exclusively, relates to the welding of a stiffener and a skin both of which are made of a composite comprising reinforcing fibres in a thermoplastic matrix, the stiffener having an omega-shaped cross section.
2. Description of the Prior Art
The operation for welding a stiffener to a skin, both of which are made of a composite comprising a thermoplastic matrix, requires that at least the interface between the skin and the stiffener be heated to the melting point of the polymer forming the matrix of the skin or stiffener.
Under these conditions, the mechanical strength of said matrix is completely reduced, and, if it is not supported, the stiffener is liable to collapse under its own weight, even in the absence of an applied pressure. Moreover, since thermoplastic polymers have a tendency to expand when heated to their melting point, the volume of a part heated to this temperature during such an operation must be strictly limited, for example by way of tooling, so as to prevent defects appearing in the parts.
Thus, carrying out static welding of a stiffener to a skin, when said stiffener comprises a thermoplastic matrix, requires complex tooling that is expensive to produce and implement.